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<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
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  <title>Document</title>
</head>

<body>
  <div>promise</div>
  <script>
    var p = new Promise((r, e) => {
      e('123')
    })
    console.log(2222)
    let result = p.then(res => {
      console.log(res)
    },err=>{
      console.warn('090909',err)
      return '123234'
    })
    console.log(result)
    result.then(res => {
      console.log(res)
    },err=>{
      console.warn('err is', err)
    })
  </script>
</body>

</html>